Background. One third of diastolic heart failure (DHF) cases is complicated with reactive pulmonary hypertension (PH). The treatment of reactive PG should provide an influence on both the reactive component and the disturbed LV diastolic function (DF). Both tasks can be solved using sildenafil, a phosphodiesterase type 5 inhibitor (PDE5). Aim. To evaluate the effect of sildenafil on functional status, pulmonary hemodynamics, and heart DF in patients with DHF and reactive PH.
Materials and methods. The study included 50 patients with FC II–III CHF, LV
EF >50%, hi gh LV filling pressure, and reactive PH (pulmonary vascular resistance >3 Wood units and/or transpulmonary pressure gradient >15 mm Hg). Patients were randomized to a PDE5 sildenafil treatment group (n=30) and a control group (n=20). Beside the study drug, all patients received a standard therapy for CHF. Sildenafil was administered at a dose of 25 mg 3 times daily for the first three months followed by 50 mg 3 times daily for the next three months till the end of study. General clinical evaluation, 6‑min walk test (6MWT), and transthoracic EchoCG were performed for all patients at baseline and at 3 and 6 months. Results.
The PDE5 sildenafil treatment was safe, resulted in a rapid decrease in mean heart failure FC, and increased the 6MWT distance by 49±8 m (р<0.05) due to decreases in pulmonary artery systolic pressure by 17±1 mm Hg (р<0.01) and pulmonary artery wedge pressure by 2.9±1 mm Hg (р<0.05). Conclusion. Sildenafil 75–150 mg/day effectively improved the functional status and reduced pulmonary artery pressure in patients with DHF at the stage of reactive PH. In this process, the increased left heart blood flow is compensated by improved LV relaxation processes, which allows avoiding an increase in left atrial pressure.